diff --git a/TwinCAT3.gitignore b/TwinCAT3.gitignore
index 07fefa11..93342d6e 100644
--- a/TwinCAT3.gitignore
+++ b/TwinCAT3.gitignore
@@ -43,6 +43,10 @@ LineIDs.dbg.bak
 **/_Deployment/
 **/_Repository/
 
+# To include a specific library directory (i.e. third party/custom libs), 
+# use pattern `!/**/_Libraries/<directory name>/` i.e. `!/**/_Libraries/www.tcunit.org/`
+# 
+
 # VS Shell project specific files and folders
 **/.vs/
 *.~u